As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM, APU FAULT LIGHT AND AUTO SHUTDOWN AT FL 340. RESTART AND RAN OK AT FL 300 PRIOR TO AUTO SHUTDOWN, APU DID START AND RUN FOR APPROX 10 MIN AT FL 340. PERFORMED FIM 49-11-00, NO DEFECTS NOTED. PRECAUTIONARY REPLACED AIR TEMP SENSOR PER AMM49-94-01. OPS CK LEAK CK OK. WIRING CHECKED ON PINS E4 AND E5 AND PINS A AND B NORMAL AT ECU CONNECTOR D408B.